The present disclosure relates to compressors and specifically to turbo-compressors. Embodiments disclosed herein relate to so-called wet-gas turbo-compressors, i.e. turbomachines which are designed for processing a gas, which contains liquid contaminants in the form of droplets, and sometimes also solid contaminants.
Turbomachines contain elements, which are particularly sensitive to solid and/or liquid particles. Typical components, which must be protected against the penetration of solid and/or liquid matter in a turbomachine, such as a centrifugal compressor, include, but are not limited to, active magnetic bearings, oil bearings, electric motors and the like. Typically, such components can be integrated in a turbomachine casing, e.g. in a compartment, which is separated by a compartment housing the compressor impellers and wherein wet gas is processed.
Sealing arrangements and devices are usually provided to separate a first compartment containing the compressor impellers from adjacent compartments containing contaminant-sensitive components, such as bearing and electric motors. In some known embodiments buffer seals are used for isolating a compartment containing one or more contaminant-sensitive components from a compartment containing the compressor, and more specifically the compressor impellers, through which contaminated gas, i.e. gas containing contaminants in the form of liquid and/or solid particles, is processed.
Dry gas is delivered to the buffer seals, to generate a gas barrier between the two compartments aimed at preventing the ingress of contaminants from the compressor compartment into the protected compartments containing the contaminant-sensitive component(s) of the compressor.
Dry gas is also used in so-called dry gas seals, which are provided for effectively separate a compressor inner volume from the surrounding environment, for example.
Dry gas is sometimes provided from an external source of clean gas. Particularly in off-shore installations providing a source of clean dry gas is, however, costly exercise, since no such source is available near the off-shore installation. Systems have therefore been developed, which use the same gas processed by the compressor to provide dry gas to the buffer seals. Gas is extracted from the compressor, cleaned and conditioned in a dry gas skid or the like and subsequently delivered to the buffer seals.
There is still a need for improving these systems and more efficiently provide various components of the compressor with dry gas extracted from the main gas flow processed by the compressor.